Conventional devices, such as a slide bolt, barrel bolt, door chain or interlocking levers, generally require only one or two serious blows before the device will fail allowing an intruder to break down the lock and enter. All of these devices provide a false sense of security to the occupant in that the occupant believes that the device will prevent intrusion when in fact only one or two serious blows are required to break down the lock.
Abutment swivel doorstops have been disclosed in U.S. Pat. No. Re. 29,162. This device uses a stop bar which is rotatable into a door blocking position by engagement of a rib and groove latch. Although novel, these doorstops did not attract any serious commercial success as the doorstop did not improve upon the security of the door beyond conventional devices. The device did not have sufficient strength to prevent an intruder from breaking the device.
Improvements were made to this particular doorstop and are more fully described in U.S. Pat. No. 4,322,100. Several improvements were made which addressed the strength problem. However, these improvements did not seriously increase the strength of the doorstop above other conventional security devices.
More recently, a device has come onto the market which is available from Winner Corporation and sold under the trademark DOORCLUB. Although this device exhibits improved strength characteristics in terms of withstanding numerous blows before failure, the device is large, bulky, expensive and requires sophisticated equipment for installation on the floor in front of the door. This installation requirement and size detracts from the salability of the product.